1. Field of the Invention
The present invention relates to an image forming apparatus which forms an image on a sheet.
2. Description of the Related Art
An image forming apparatus, such as a printer and a copier, includes a containing cassette as a containing portion in which sheets are contained in a stacked manner. The sheet is fed from the containing cassette and an image is formed on the sheet. When the containing cassette is replenished with sheets, the containing cassette is pulled from an apparatus main body of the image forming apparatus. Further, it is necessary to remove the containing cassette from the apparatus main body for, for example, the maintenance of the apparatus.
A configuration provided with a stopper for regulating removal of the containing cassette from the apparatus main body when the containing cassette is pulled from the apparatus main body has been proposed. By regulating the pulling of the containing cassette by the stopper on the way, replenishment of the sheets and the like may be performed easily. By releasing the stopper and removing the containing cassette from the apparatus main body, maintenance and the like may be performed easily. Japanese Patent No. 3516376 proposes a configuration in which a user lifts a containing cassette and releases regulation of a stopper, whereby the containing cassette becomes removable from the apparatus main body. Japanese Patent No. 3571910 proposes a configuration in which a stopper for regulating removal is swingably attached to a containing cassette and, when a user manually moves the stopper to a position at which regulation is released, the containing cassette becomes removable.
In the configuration of Japanese Patent No. 3516376, when the user lifts the containing cassette, the containing cassette becomes removable. In this apparatus, however, there is a possibility that the containing cassette is removed from the apparatus main body even when the user does not intend to remove the containing cassette. In the configuration of Japanese Patent No. 3571910, there is a possibility that the user makes the stopper swing unintentionally and the containing cassette may be removed.
In a case in which the containing cassette is unintendedly removed in this manner, it is possible that, for example, the user will be at a loss how to attach the removed containing cassette to the apparatus main body again. It is also possible that the user breaks the apparatus in an attempt to attach the containing cassette by force without knowing how to attach the same.